﻿/*
* Copyright (c) 2006-2007 Erin Catto http:
*
* This software is provided 'as-is', without any express or implied
* warranty.  In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked, and must not be
* misrepresented the original software.
* 3. This notice may not be removed or altered from any source distribution.
*
* Converted for The Render Engine v2.0
* Aug. 4, 2010 Brett Fattori
*/

Engine.include("/physics/common/b2Settings.js");
Engine.include("/physics/common/math/b2Math.js");
Engine.include("/physics/common/math/b2Vec2.js");

Engine.include("/physics/dynamics/b2World.js");

Engine.include("/physics/dynamics/joints/b2Joint.js");
Engine.include("/physics/dynamics/joints/b2JointNode.js");


Engine.initObject("b2PulleyJoint", "b2Joint", function() {

	var b2PulleyJoint = b2Joint.extend({

		m_ground: null,
		m_groundAnchor1: null,
		m_groundAnchor2: null,
		m_localAnchor1: null,
		m_localAnchor2: null,
	
		m_u1: null,
		m_u2: null,
	
		m_constant: null,
		m_ratio: null,
	
		m_maxLength1: null,
		m_maxLength2: null,
	
		// Effective masses
		m_pulleyMass: null,
		m_limitMass1: null,
		m_limitMass2: null,
	
		// Impulses for accumulation/warm starting.
		m_pulleyImpulse: null,
		m_limitImpulse1: null,
		m_limitImpulse2: null,
	
		// Position impulses for accumulation.
		m_limitPositionImpulse1: null,
		m_limitPositionImpulse2: null,
	
		m_limitState1: 0,
		m_limitState2: 0,
	
		constructor: function(def) {
			// The constructor for b2Joint
			// initialize instance variables for references
			this.m_node1 = new b2JointNode();
			this.m_node2 = new b2JointNode();
			//
			this.m_type = def.type;
			this.m_prev = null;
			this.m_next = null;
			this.m_body1 = def.body1;
			this.m_body2 = def.body2;
			this.m_collideConnected = def.collideConnected;
			this.m_islandFlag = false;
			this.m_userData = def.userData;
			//
	
			// initialize instance variables for references
			this.m_groundAnchor1 = new b2Vec2();
			this.m_groundAnchor2 = new b2Vec2();
			this.m_localAnchor1 = new b2Vec2();
			this.m_localAnchor2 = new b2Vec2();
			this.m_u1 = new b2Vec2();
			this.m_u2 = new b2Vec2();
			//
	
	
			// parent
			//super(def);
	
			var tMat;
			var tX;
			var tY;
	
			this.m_ground = this.m_body1.m_world.m_groundBody;
			//this.m_groundAnchor1 = def.groundPoint1 - this.m_ground.m_position;
			this.m_groundAnchor1.x = def.groundPoint1.x - this.m_ground.m_position.x;
			this.m_groundAnchor1.y = def.groundPoint1.y - this.m_ground.m_position.y;
			//this.m_groundAnchor2 = def.groundPoint2 - this.m_ground.m_position;
			this.m_groundAnchor2.x = def.groundPoint2.x - this.m_ground.m_position.x;
			this.m_groundAnchor2.y = def.groundPoint2.y - this.m_ground.m_position.y;
			//this.m_localAnchor1 = b2MulT(this.m_body1.m_R, def.anchorPoint1 - this.m_body1.m_position);
			tMat = this.m_body1.m_R;
			tX = def.anchorPoint1.x - this.m_body1.m_position.x;
			tY = def.anchorPoint1.y - this.m_body1.m_position.y;
			this.m_localAnchor1.x = tX*tMat.col1.x + tY*tMat.col1.y;
			this.m_localAnchor1.y = tX*tMat.col2.x + tY*tMat.col2.y;
			//this.m_localAnchor2 = b2MulT(this.m_body2.m_R, def.anchorPoint2 - this.m_body2.m_position);
			tMat = this.m_body2.m_R;
			tX = def.anchorPoint2.x - this.m_body2.m_position.x;
			tY = def.anchorPoint2.y - this.m_body2.m_position.y;
			this.m_localAnchor2.x = tX*tMat.col1.x + tY*tMat.col1.y;
			this.m_localAnchor2.y = tX*tMat.col2.x + tY*tMat.col2.y;
	
			this.m_ratio = def.ratio;
	
			//var d1 = def.groundPoint1 - def.anchorPoint1;
			tX = def.groundPoint1.x - def.anchorPoint1.x;
			tY = def.groundPoint1.y - def.anchorPoint1.y;
			var d1Len = Math.sqrt(tX*tX + tY*tY);
			//var d2 = def.groundPoint2 - def.anchorPoint2;
			tX = def.groundPoint2.x - def.anchorPoint2.x;
			tY = def.groundPoint2.y - def.anchorPoint2.y;
			var d2Len = Math.sqrt(tX*tX + tY*tY);
	
			var length1 = b2Math.b2Max(0.5 * b2PulleyJoint.b2_minPulleyLength, d1Len);
			var length2 = b2Math.b2Max(0.5 * b2PulleyJoint.b2_minPulleyLength, d2Len);
	
			this.m_constant = length1 + this.m_ratio * length2;
	
			this.m_maxLength1 = b2Math.b2Clamp(def.maxLength1, length1, this.m_constant - this.m_ratio * b2PulleyJoint.b2_minPulleyLength);
			this.m_maxLength2 = b2Math.b2Clamp(def.maxLength2, length2, (this.m_constant - b2PulleyJoint.b2_minPulleyLength) / this.m_ratio);
	
			this.m_pulleyImpulse = 0.0;
			this.m_limitImpulse1 = 0.0;
			this.m_limitImpulse2 = 0.0;
		},	
		
		GetAnchor1: function() {
			//return this.m_body1->m_position + b2Mul(this.m_body1->m_R, this.m_localAnchor1);
			var tMat = this.m_body1.m_R;
			return new b2Vec2(	this.m_body1.m_position.x + (tMat.col1.x * this.m_localAnchor1.x + tMat.col2.x * this.m_localAnchor1.y),
								this.m_body1.m_position.y + (tMat.col1.y * this.m_localAnchor1.x + tMat.col2.y * this.m_localAnchor1.y));
		},
		
		GetAnchor2: function() {
			//return this.m_body2->m_position + b2Mul(this.m_body2->m_R, this.m_localAnchor2);
			var tMat = this.m_body2.m_R;
			return new b2Vec2(	this.m_body2.m_position.x + (tMat.col1.x * this.m_localAnchor2.x + tMat.col2.x * this.m_localAnchor2.y),
								this.m_body2.m_position.y + (tMat.col1.y * this.m_localAnchor2.x + tMat.col2.y * this.m_localAnchor2.y));
		},
	
		GetGroundPoint1: function() {
			//return this.m_ground->m_position + this.m_groundAnchor1;
			return new b2Vec2(this.m_ground.m_position.x + this.m_groundAnchor1.x, this.m_ground.m_position.y + this.m_groundAnchor1.y);
		},
		
		GetGroundPoint2: function() {
			return new b2Vec2(this.m_ground.m_position.x + this.m_groundAnchor2.x, this.m_ground.m_position.y + this.m_groundAnchor2.y);
		},
	
		GetReactionForce: function(invTimeStep) {
			//b2Vec2 F(0.0f, 0.0f);
			return new b2Vec2();
		},
		
		GetReactionTorque: function(invTimeStep){
			return 0.0;
		},
	
		GetLength1: function() {
			var tMat;
			//b2Vec2 p = this.m_body1->m_position + b2Mul(this.m_body1->m_R, this.m_localAnchor1);
			tMat = this.m_body1.m_R;
			var pX = this.m_body1.m_position.x + (tMat.col1.x * this.m_localAnchor1.x + tMat.col2.x * this.m_localAnchor1.y);
			var pY = this.m_body1.m_position.y + (tMat.col1.y * this.m_localAnchor1.x + tMat.col2.y * this.m_localAnchor1.y);
			//b2Vec2 s = this.m_ground->m_position + this.m_groundAnchor1;
			//b2Vec2 d = p - s;
			var dX = pX - (this.m_ground.m_position.x + this.m_groundAnchor1.x);
			var dY = pY - (this.m_ground.m_position.y + this.m_groundAnchor1.y);
			return Math.sqrt(dX*dX + dY*dY);
		},
		
		GetLength2: function(){
			var tMat;
			//b2Vec2 p = this.m_body2->m_position + b2Mul(this.m_body2->m_R, this.m_localAnchor2);
			tMat = this.m_body2.m_R;
			var pX = this.m_body2.m_position.x + (tMat.col1.x * this.m_localAnchor2.x + tMat.col2.x * this.m_localAnchor2.y);
			var pY = this.m_body2.m_position.y + (tMat.col1.y * this.m_localAnchor2.x + tMat.col2.y * this.m_localAnchor2.y);
			//b2Vec2 s = this.m_ground->m_position + this.m_groundAnchor2;
			//b2Vec2 d = p - s;
			var dX = pX - (this.m_ground.m_position.x + this.m_groundAnchor2.x);
			var dY = pY - (this.m_ground.m_position.y + this.m_groundAnchor2.y);
			return Math.sqrt(dX*dX + dY*dY);
		},
	
		GetRatio: function() {
			return this.m_ratio;
		},
		
		PrepareVelocitySolver: function() {
			var b1 = this.m_body1;
			var b2 = this.m_body2;
	
			var tMat;
	
			//b2Vec2 r1 = b2Mul(b1->m_R, this.m_localAnchor1);
			tMat = b1.m_R;
			var r1X = tMat.col1.x * this.m_localAnchor1.x + tMat.col2.x * this.m_localAnchor1.y;
			var r1Y = tMat.col1.y * this.m_localAnchor1.x + tMat.col2.y * this.m_localAnchor1.y;
			//b2Vec2 r2 = b2Mul(b2->m_R, this.m_localAnchor2);
			tMat = b2.m_R;
			var r2X = tMat.col1.x * this.m_localAnchor2.x + tMat.col2.x * this.m_localAnchor2.y;
			var r2Y = tMat.col1.y * this.m_localAnchor2.x + tMat.col2.y * this.m_localAnchor2.y;
	
			//b2Vec2 p1 = b1->m_position + r1;
			var p1X = b1.m_position.x + r1X;
			var p1Y = b1.m_position.y + r1Y;
			//b2Vec2 p2 = b2->m_position + r2;
			var p2X = b2.m_position.x + r2X;
			var p2Y = b2.m_position.y + r2Y;
	
			//b2Vec2 s1 = this.m_ground->m_position + this.m_groundAnchor1;
			var s1X = this.m_ground.m_position.x + this.m_groundAnchor1.x;
			var s1Y = this.m_ground.m_position.y + this.m_groundAnchor1.y;
			//b2Vec2 s2 = this.m_ground->m_position + this.m_groundAnchor2;
			var s2X = this.m_ground.m_position.x + this.m_groundAnchor2.x;
			var s2Y = this.m_ground.m_position.y + this.m_groundAnchor2.y;
	
			// Get the pulley axes.
			//this.m_u1 = p1 - s1;
			this.m_u1.Set(p1X - s1X, p1Y - s1Y);
			//this.m_u2 = p2 - s2;
			this.m_u2.Set(p2X - s2X, p2Y - s2Y);
	
			var length1 = this.m_u1.Length();
			var length2 = this.m_u2.Length();
	
			if (length1 > b2Settings.b2_linearSlop)
			{
				//this.m_u1 *= 1.0f / length1;
				this.m_u1.Multiply(1.0 / length1);
			}
			else
			{
				this.m_u1.SetZero();
			}
	
			if (length2 > b2Settings.b2_linearSlop)
			{
				//this.m_u2 *= 1.0f / length2;
				this.m_u2.Multiply(1.0 / length2);
			}
			else
			{
				this.m_u2.SetZero();
			}
	
			if (length1 < this.m_maxLength1)
			{
				this.m_limitState1 = b2Joint.e_inactiveLimit;
				this.m_limitImpulse1 = 0.0;
			}
			else
			{
				this.m_limitState1 = b2Joint.e_atUpperLimit;
				this.m_limitPositionImpulse1 = 0.0;
			}
	
			if (length2 < this.m_maxLength2)
			{
				this.m_limitState2 = b2Joint.e_inactiveLimit;
				this.m_limitImpulse2 = 0.0;
			}
			else
			{
				this.m_limitState2 = b2Joint.e_atUpperLimit;
				this.m_limitPositionImpulse2 = 0.0;
			}
	
			// Compute effective mass.
			//var cr1u1 = b2Cross(r1, this.m_u1);
			var cr1u1 = r1X * this.m_u1.y - r1Y * this.m_u1.x;
			//var cr2u2 = b2Cross(r2, this.m_u2);
			var cr2u2 = r2X * this.m_u2.y - r2Y * this.m_u2.x;
	
			this.m_limitMass1 = b1.m_invMass + b1.m_invI * cr1u1 * cr1u1;
			this.m_limitMass2 = b2.m_invMass + b2.m_invI * cr2u2 * cr2u2;
			this.m_pulleyMass = this.m_limitMass1 + this.m_ratio * this.m_ratio * this.m_limitMass2;
			//b2Settings.b2Assert(this.m_limitMass1 > Number.MIN_VALUE);
			//b2Settings.b2Assert(this.m_limitMass2 > Number.MIN_VALUE);
			//b2Settings.b2Assert(this.m_pulleyMass > Number.MIN_VALUE);
			this.m_limitMass1 = 1.0 / this.m_limitMass1;
			this.m_limitMass2 = 1.0 / this.m_limitMass2;
			this.m_pulleyMass = 1.0 / this.m_pulleyMass;
	
			// Warm starting.
			//b2Vec2 P1 = (-this.m_pulleyImpulse - this.m_limitImpulse1) * this.m_u1;
			var P1X = (-this.m_pulleyImpulse - this.m_limitImpulse1) * this.m_u1.x;
			var P1Y = (-this.m_pulleyImpulse - this.m_limitImpulse1) * this.m_u1.y;
			//b2Vec2 P2 = (-this.m_ratio * this.m_pulleyImpulse - this.m_limitImpulse2) * this.m_u2;
			var P2X = (-this.m_ratio * this.m_pulleyImpulse - this.m_limitImpulse2) * this.m_u2.x;
			var P2Y = (-this.m_ratio * this.m_pulleyImpulse - this.m_limitImpulse2) * this.m_u2.y;
			//b1.m_linearVelocity += b1.m_invMass * P1;
			b1.m_linearVelocity.x += b1.m_invMass * P1X;
			b1.m_linearVelocity.y += b1.m_invMass * P1Y;
			//b1.m_angularVelocity += b1.m_invI * b2Cross(r1, P1);
			b1.m_angularVelocity += b1.m_invI * (r1X * P1Y - r1Y * P1X);
			//b2.m_linearVelocity += b2.m_invMass * P2;
			b2.m_linearVelocity.x += b2.m_invMass * P2X;
			b2.m_linearVelocity.y += b2.m_invMass * P2Y;
			//b2.m_angularVelocity += b2.m_invI * b2Cross(r2, P2);
			b2.m_angularVelocity += b2.m_invI * (r2X * P2Y - r2Y * P2X);
		},
	
		SolveVelocityConstraints: function(step) {
			var b1 = this.m_body1;
			var b2 = this.m_body2;
	
			var tMat;
	
			//var r1 = b2Mul(b1.m_R, this.m_localAnchor1);
			tMat = b1.m_R;
			var r1X = tMat.col1.x * this.m_localAnchor1.x + tMat.col2.x * this.m_localAnchor1.y;
			var r1Y = tMat.col1.y * this.m_localAnchor1.x + tMat.col2.y * this.m_localAnchor1.y;
			//var r2 = b2Mul(b2.m_R, this.m_localAnchor2);
			tMat = b2.m_R;
			var r2X = tMat.col1.x * this.m_localAnchor2.x + tMat.col2.x * this.m_localAnchor2.y;
			var r2Y = tMat.col1.y * this.m_localAnchor2.x + tMat.col2.y * this.m_localAnchor2.y;
	
			// temp vars
			var v1X;
			var v1Y;
			var v2X;
			var v2Y;
			var P1X;
			var P1Y;
			var P2X;
			var P2Y;
			var Cdot;
			var impulse;
			var oldLimitImpulse;
	
			//{
				//b2Vec2 v1 = b1->m_linearVelocity + b2Cross(b1->m_angularVelocity, r1);
				v1X = b1.m_linearVelocity.x + (-b1.m_angularVelocity * r1Y);
				v1Y = b1.m_linearVelocity.y + (b1.m_angularVelocity * r1X);
				//b2Vec2 v2 = b2->m_linearVelocity + b2Cross(b2->m_angularVelocity, r2);
				v2X = b2.m_linearVelocity.x + (-b2.m_angularVelocity * r2Y);
				v2Y = b2.m_linearVelocity.y + (b2.m_angularVelocity * r2X);
	
				//Cdot = -b2Dot(this.m_u1, v1) - this.m_ratio * b2Dot(this.m_u2, v2);
				Cdot = -(this.m_u1.x * v1X + this.m_u1.y * v1Y) - this.m_ratio * (this.m_u2.x * v2X + this.m_u2.y * v2Y);
				impulse = -this.m_pulleyMass * Cdot;
				this.m_pulleyImpulse += impulse;
	
				//b2Vec2 P1 = -impulse * this.m_u1;
				P1X = -impulse * this.m_u1.x;
				P1Y = -impulse * this.m_u1.y;
				//b2Vec2 P2 = -this.m_ratio * impulse * this.m_u2;
				P2X = -this.m_ratio * impulse * this.m_u2.x;
				P2Y = -this.m_ratio * impulse * this.m_u2.y;
				//b1.m_linearVelocity += b1.m_invMass * P1;
				b1.m_linearVelocity.x += b1.m_invMass * P1X;
				b1.m_linearVelocity.y += b1.m_invMass * P1Y;
				//b1.m_angularVelocity += b1.m_invI * b2Cross(r1, P1);
				b1.m_angularVelocity += b1.m_invI * (r1X * P1Y - r1Y * P1X);
				//b2.m_linearVelocity += b2.m_invMass * P2;
				b2.m_linearVelocity.x += b2.m_invMass * P2X;
				b2.m_linearVelocity.y += b2.m_invMass * P2Y;
				//b2.m_angularVelocity += b2.m_invI * b2Cross(r2, P2);
				b2.m_angularVelocity += b2.m_invI * (r2X * P2Y - r2Y * P2X);
			//}
	
			if (this.m_limitState1 == b2Joint.e_atUpperLimit)
			{
				//b2Vec2 v1 = b1->m_linearVelocity + b2Cross(b1->m_angularVelocity, r1);
				v1X = b1.m_linearVelocity.x + (-b1.m_angularVelocity * r1Y);
				v1Y = b1.m_linearVelocity.y + (b1.m_angularVelocity * r1X);
	
				//float32 Cdot = -b2Dot(this.m_u1, v1);
				Cdot = -(this.m_u1.x * v1X + this.m_u1.y * v1Y);
				impulse = -this.m_limitMass1 * Cdot;
				oldLimitImpulse = this.m_limitImpulse1;
				this.m_limitImpulse1 = b2Math.b2Max(0.0, this.m_limitImpulse1 + impulse);
				impulse = this.m_limitImpulse1 - oldLimitImpulse;
				//b2Vec2 P1 = -impulse * this.m_u1;
				P1X = -impulse * this.m_u1.x;
				P1Y = -impulse * this.m_u1.y;
				//b1.m_linearVelocity += b1->m_invMass * P1;
				b1.m_linearVelocity.x += b1.m_invMass * P1X;
				b1.m_linearVelocity.y += b1.m_invMass * P1Y;
				//b1.m_angularVelocity += b1->m_invI * b2Cross(r1, P1);
				b1.m_angularVelocity += b1.m_invI * (r1X * P1Y - r1Y * P1X);
			}
	
			if (this.m_limitState2 == b2Joint.e_atUpperLimit)
			{
				//b2Vec2 v2 = b2->m_linearVelocity + b2Cross(b2->m_angularVelocity, r2);
				v2X = b2.m_linearVelocity.x + (-b2.m_angularVelocity * r2Y);
				v2Y = b2.m_linearVelocity.y + (b2.m_angularVelocity * r2X);
	
				//float32 Cdot = -b2Dot(this.m_u2, v2);
				Cdot = -(this.m_u2.x * v2X + this.m_u2.y * v2Y);
				impulse = -this.m_limitMass2 * Cdot;
				oldLimitImpulse = this.m_limitImpulse2;
				this.m_limitImpulse2 = b2Math.b2Max(0.0, this.m_limitImpulse2 + impulse);
				impulse = this.m_limitImpulse2 - oldLimitImpulse;
				//b2Vec2 P2 = -impulse * this.m_u2;
				P2X = -impulse * this.m_u2.x;
				P2Y = -impulse * this.m_u2.y;
				//b2->m_linearVelocity += b2->m_invMass * P2;
				b2.m_linearVelocity.x += b2.m_invMass * P2X;
				b2.m_linearVelocity.y += b2.m_invMass * P2Y;
				//b2->m_angularVelocity += b2->m_invI * b2Cross(r2, P2);
				b2.m_angularVelocity += b2.m_invI * (r2X * P2Y - r2Y * P2X);
			}
		},
	
		SolvePositionConstraints: function() {
			var b1 = this.m_body1;
			var b2 = this.m_body2;
	
			var tMat;
	
			//b2Vec2 s1 = this.m_ground->m_position + this.m_groundAnchor1;
			var s1X = this.m_ground.m_position.x + this.m_groundAnchor1.x;
			var s1Y = this.m_ground.m_position.y + this.m_groundAnchor1.y;
			//b2Vec2 s2 = this.m_ground->m_position + this.m_groundAnchor2;
			var s2X = this.m_ground.m_position.x + this.m_groundAnchor2.x;
			var s2Y = this.m_ground.m_position.y + this.m_groundAnchor2.y;
	
			// temp vars
			var r1X;
			var r1Y;
			var r2X;
			var r2Y;
			var p1X;
			var p1Y;
			var p2X;
			var p2Y;
			var length1;
			var length2;
			var C;
			var impulse;
			var oldLimitPositionImpulse;
	
			var linearError = 0.0;
	
			{
				//var r1 = b2Mul(b1.m_R, this.m_localAnchor1);
				tMat = b1.m_R;
				r1X = tMat.col1.x * this.m_localAnchor1.x + tMat.col2.x * this.m_localAnchor1.y;
				r1Y = tMat.col1.y * this.m_localAnchor1.x + tMat.col2.y * this.m_localAnchor1.y;
				//var r2 = b2Mul(b2.m_R, this.m_localAnchor2);
				tMat = b2.m_R;
				r2X = tMat.col1.x * this.m_localAnchor2.x + tMat.col2.x * this.m_localAnchor2.y;
				r2Y = tMat.col1.y * this.m_localAnchor2.x + tMat.col2.y * this.m_localAnchor2.y;
	
				//b2Vec2 p1 = b1->m_position + r1;
				p1X = b1.m_position.x + r1X;
				p1Y = b1.m_position.y + r1Y;
				//b2Vec2 p2 = b2->m_position + r2;
				p2X = b2.m_position.x + r2X;
				p2Y = b2.m_position.y + r2Y;
	
				// Get the pulley axes.
				//this.m_u1 = p1 - s1;
				this.m_u1.Set(p1X - s1X, p1Y - s1Y);
				//this.m_u2 = p2 - s2;
				this.m_u2.Set(p2X - s2X, p2Y - s2Y);
	
				length1 = this.m_u1.Length();
				length2 = this.m_u2.Length();
	
				if (length1 > b2Settings.b2_linearSlop)
				{
					//this.m_u1 *= 1.0f / length1;
					this.m_u1.Multiply( 1.0 / length1 );
				}
				else
				{
					this.m_u1.SetZero();
				}
	
				if (length2 > b2Settings.b2_linearSlop)
				{
					//this.m_u2 *= 1.0f / length2;
					this.m_u2.Multiply( 1.0 / length2 );
				}
				else
				{
					this.m_u2.SetZero();
				}
	
				C = this.m_constant - length1 - this.m_ratio * length2;
				linearError = b2Math.b2Max(linearError, Math.abs(C));
				C = b2Math.b2Clamp(C, -b2Settings.b2_maxLinearCorrection, b2Settings.b2_maxLinearCorrection);
				impulse = -this.m_pulleyMass * C;
	
				p1X = -impulse * this.m_u1.x;
				p1Y = -impulse * this.m_u1.y;
				p2X = -this.m_ratio * impulse * this.m_u2.x;
				p2Y = -this.m_ratio * impulse * this.m_u2.y;
	
				b1.m_position.x += b1.m_invMass * p1X;
				b1.m_position.y += b1.m_invMass * p1Y;
				b1.m_rotation += b1.m_invI * (r1X * p1Y - r1Y * p1X);
				b2.m_position.x += b2.m_invMass * p2X;
				b2.m_position.y += b2.m_invMass * p2Y;
				b2.m_rotation += b2.m_invI * (r2X * p2Y - r2Y * p2X);
	
				b1.m_R.Set(b1.m_rotation);
				b2.m_R.Set(b2.m_rotation);
			}
	
			if (this.m_limitState1 == b2Joint.e_atUpperLimit)
			{
				//b2Vec2 r1 = b2Mul(b1->m_R, this.m_localAnchor1);
				tMat = b1.m_R;
				r1X = tMat.col1.x * this.m_localAnchor1.x + tMat.col2.x * this.m_localAnchor1.y;
				r1Y = tMat.col1.y * this.m_localAnchor1.x + tMat.col2.y * this.m_localAnchor1.y;
				//b2Vec2 p1 = b1->m_position + r1;
				p1X = b1.m_position.x + r1X;
				p1Y = b1.m_position.y + r1Y;
	
				//this.m_u1 = p1 - s1;
				this.m_u1.Set(p1X - s1X, p1Y - s1Y);
	
				length1 = this.m_u1.Length();
	
				if (length1 > b2Settings.b2_linearSlop)
				{
					//this.m_u1 *= 1.0 / length1;
					this.m_u1.x *= 1.0 / length1;
					this.m_u1.y *= 1.0 / length1;
				}
				else
				{
					this.m_u1.SetZero();
				}
	
				C = this.m_maxLength1 - length1;
				linearError = b2Math.b2Max(linearError, -C);
				C = b2Math.b2Clamp(C + b2Settings.b2_linearSlop, -b2Settings.b2_maxLinearCorrection, 0.0);
				impulse = -this.m_limitMass1 * C;
				oldLimitPositionImpulse = this.m_limitPositionImpulse1;
				this.m_limitPositionImpulse1 = b2Math.b2Max(0.0, this.m_limitPositionImpulse1 + impulse);
				impulse = this.m_limitPositionImpulse1 - oldLimitPositionImpulse;
	
				//P1 = -impulse * this.m_u1;
				p1X = -impulse * this.m_u1.x;
				p1Y = -impulse * this.m_u1.y;
	
				b1.m_position.x += b1.m_invMass * p1X;
				b1.m_position.y += b1.m_invMass * p1Y;
				//b1.m_rotation += b1.m_invI * b2Cross(r1, P1);
				b1.m_rotation += b1.m_invI * (r1X * p1Y - r1Y * p1X);
				b1.m_R.Set(b1.m_rotation);
			}
	
			if (this.m_limitState2 == b2Joint.e_atUpperLimit)
			{
				//b2Vec2 r2 = b2Mul(b2->m_R, this.m_localAnchor2);
				tMat = b2.m_R;
				r2X = tMat.col1.x * this.m_localAnchor2.x + tMat.col2.x * this.m_localAnchor2.y;
				r2Y = tMat.col1.y * this.m_localAnchor2.x + tMat.col2.y * this.m_localAnchor2.y;
				//b2Vec2 p2 = b2->m_position + r2;
				p2X = b2.m_position.x + r2X;
				p2Y = b2.m_position.y + r2Y;
	
				//this.m_u2 = p2 - s2;
				this.m_u2.Set(p2X - s2X, p2Y - s2Y);
	
				length2 = this.m_u2.Length();
	
				if (length2 > b2Settings.b2_linearSlop)
				{
					//this.m_u2 *= 1.0 / length2;
					this.m_u2.x *= 1.0 / length2;
					this.m_u2.y *= 1.0 / length2;
				}
				else
				{
					this.m_u2.SetZero();
				}
	
				C = this.m_maxLength2 - length2;
				linearError = b2Math.b2Max(linearError, -C);
				C = b2Math.b2Clamp(C + b2Settings.b2_linearSlop, -b2Settings.b2_maxLinearCorrection, 0.0);
				impulse = -this.m_limitMass2 * C;
				oldLimitPositionImpulse = this.m_limitPositionImpulse2;
				this.m_limitPositionImpulse2 = b2Math.b2Max(0.0, this.m_limitPositionImpulse2 + impulse);
				impulse = this.m_limitPositionImpulse2 - oldLimitPositionImpulse;
	
				//P2 = -impulse * this.m_u2;
				p2X = -impulse * this.m_u2.x;
				p2Y = -impulse * this.m_u2.y;
	
				//b2.m_position += b2.m_invMass * P2;
				b2.m_position.x += b2.m_invMass * p2X;
				b2.m_position.y += b2.m_invMass * p2Y;
				//b2.m_rotation += b2.m_invI * b2Cross(r2, P2);
				b2.m_rotation += b2.m_invI * (r2X * p2Y - r2Y * p2X);
				b2.m_R.Set(b2.m_rotation);
			}
	
			return linearError < b2Settings.b2_linearSlop;
		}
		
	}, {
		
		resolved: function() {
	      b2PulleyJoint.b2_minPulleyLength = b2Settings.b2_lengthUnitsPerMeter;
		},
		
		b2_minPulleyLength: null
		
	});

	return b2PulleyJoint;

});
